• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.746-749
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• 2004

A new-type of FRP-concrete composite bridge deck system is proposed and its behaviors are experimentally studied. The new-typedeck consists of FRP as a permanent form and main tension resisting member and concrete as a compression resisting member. A suitable bonding method such as silica coating is applied to the interface between FRP and concrete to ensure composite behavior. The proposed deck system uses the box-shape FRP member, while a typical FRP-concrete composite deck uses the I-shape FRP member. Theproposed deck system has inherent advantages of a FRP-concrete composite deck like corrosion free and easy construction. The new-type deck shows the equal performances compared to a previous one, and has the advantage of reducing self-weight. In this study, the static tests on 3-span FRP-concrete decks in full scale are carried out, so that load-displacement relation, stress distribution, failure mode and design criteria are analyzed. The test results show that the deflection design criterion (L/800, L: span length) is satisfied at the service load state. No concrete tensile crack occurs in the negative moment region above the main girder, regardless of no tensile reinforcement at upper concrete portion.

• Animal Systematics, Evolution and Diversity
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• v.33 no.4
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• pp.246-255
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• 2017

Three freshwater ciliates, Lembadion lucens (Maskell, 1887) Kahl, 1931, L. bullinum ($M{\ddot{u}}ller$, 1786) Perty, 1849, and L. magnum (Stokes, 1887) Kahl, 1931, belonging to the genus Lembadion Perty, 1849 are newly reported from Korea with detailed descriptions and illustrations based on live observation and protargol impregnation. Lembadion lucens is characterized by following characteristics: $52-91{\times}33-64{\mu}m$ body size in vivo; ovoid and slightly asymmetric body shape; 27-49 somatic kineties; and 55-80% of whole pellicle covered with meridional lines with rectangular meshes in posterior portion. Lembadion bullinum is distinguishable from its congeners by its body size of $110-130{\times}60-73{\mu}m$ in vivo; ovoid body shape; oral aperture occupying about four-fifths of ventral side; 48-55 somatic ciliary rows; meridional lines with rectangular meshes except anterior portion (about 16% of body) on pellicle. Lembadion magnum is also characterized by its body size of $70-90{\times}37-50{\mu}m$ in vivo; obliquely asymmetric anterior end of body; oral aperture occupying about more than four-fifths of ventral surface, and opened longitudinally entire ventral surface; 45-61 somatic ciliary rows; meridional lines without rectangular meshes on whole pellicle of body. The present study is the first description of the genus Lembadion from Korea.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.1
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• pp.98-104
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• 2015

This experiment was a study of a Vortex nozzle designed to produce micro-bubbles due To investigate air self-suction and the generation of micro-bubble by the Vortex nozzle, the dimensions of air intake region, the nozzle shape, and the nozzle exit diameter ($d_n=5,7,9.2,12.3mm$)werevaried. The air self-suction rate was ~1,000 to 2,000 cc/min at the orifice nozzle (7 mm), and ~100 and ~22 cc/min at the sector nozzles (9.2 and 12.3 mm, respectively). The most bubbles were detected in the orifice nozzle, but bubbles less than $50{\mu}m$ were found in the 12.3-mm sector nozzle. The dissolved oxygen in the tank water was much greater in Case 2 than in Case 1, at both the orifice and sector nozzles. Moreover, the reduction rate of dissolved oxygen was found to be less at the sector nozzles, than at the orifice nozzle.

• Composites Research
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• v.27 no.6
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• pp.231-235
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• 2014

Autoclave processing has a good quality of product, but manufacturing cost is expansive. After curing of composite, the unwanted deformation and distortion increase the manufacturing cost by redesign of tool parts. Therefore, manufacturing cost down is a big issue in processing level. For the reduction of tool costs, it is important to investigate the effects of tool materials and tool surface conditions. In this paper, we organized user subroutine in ABAQUS to consider the thermal effects of part and tool, and the results are compared with commercial code, COMPRO. And this paper suggests reference point for the selection of tool materials to reduce manufacturing costs.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.8
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• pp.913-920
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• 2012

An efficient 3D finite element walking model that considers the detailed shapes of muscles, ligaments, bones, skin, and soles was developed based on a real computed tomography (CT) scan image of a foot, and nonlinear contact analyses were performed to investigate pressure changes. The highest pressure occurs at the rear bottom of the foot when standing and walking. The pressure on the outsole with a curved foot bottom surface is lessened and distributed over a wider area than in the case of a flat outsole. The result shows that a shoe sole shape optimized for diabetes patients can relieve the foot pressure concentration and prevent further worsening of symptoms.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.8
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• pp.1051-1056
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• 2001

Data for teat number for Landrace (L), Yorkshire (Y), crossbred of Landrace and Yorkshire (LY), and crossbred of Landrace, Yorkshire and Chinese indigenous Min Pig (LYM) were analyzed using Gibbs sampling. In Bayesian inference, flat priors and some informative priors were used to examine their influence on posterior estimates. The posterior mean estimates of heritabilities with flat priors were $0.661{\pm}0.035$ for L, $0.540{\pm}0.072$ for Y, $0.789{\pm}0.074$ for LY, and $0.577{\pm}0.058$ for LYM, and they did not differ (p>0.05) from their corresponding estimates of REML. When inverse Gamma densities for variance components were used as priors with the shape parameter of 4, the posterior estimates were still corresponding (p>0.05) to REML estimates and mean estimates using Gibbs sampling with flat priors. However, when the inverse Gamma densities with the shape parameter of 10 were utilized, some posterior estimates differed (p<0.10) from REML estimates and/or from other Gibbs mean estimates. The use of moderate degree of belief was influential to the posterior estimates, especially for Y and for LY where data sizes were small. When the data size is small, REML estimates of variance components have unknown distributions. On the other hand, Bayesian approach gives exact posterior densities of variance components. However, when the data size is small and prior knowledge is lacked, researchers should be careful with even moderate priors.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.5
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• pp.291-296
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• 2009

Ice accumulating system patterned ice-an-coil is the way of refrigerating regenerative materials on the surface of copper-tube inserted into the inside of ice-storage. The study experimented to understand ice-an-coil type ice making characteristics according to changing shape of ice making tube. The experiment were carried out under various conditions, that used brine temperature($-l0^{\circ}C$, $-6^{\circ}C$) brine flow rate(l.0m/s, 1.8m/s) and inlet water temperature($6^{\circ}C$, $12^{\circ}C$) etc. Mass of ice per making area increased according to the decrease of the brine temperature and inlet water temperature, but that was increased according to the increase of the brine flow rate. And I set up two hypotheses and compared the capacity of ice-making of the two cases; each had the same thermal area and one had an round-shaped copper tube but the other had an oval-shaped copper tube.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.5 no.3
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• pp.198-203
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• 1993

Hydraulic experiments were carried out to investigate the reflection characteristics of perforated breakwaters in regular wave conditions varying the width of wave chamber and the shape of perforated wall. It was found that the reflection coefficient of the perforated breakwater was very sensitive to the change of wave chamber width. giving its minimal value when the width of the wave chamber is approximately 0.2 times the wave length in the wave chamber. This phenomenon may be resulted from the wave resonance inside the wave chamber. The reflection coefficients slightly varied for all shapes of perforated wall. i.e., vortical slit, horizontal slit or circular hole. However, the reflection trend of the structure was not significantly affected by the shape of the perforated wall.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.26 no.2
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• pp.65-73
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• 1996

The purpose of this study was to evaluate the clinical and computed tomographic features of 7 cases of maxillofacial gunshot injuries in the suicidal patients visited the emergency room, Capital Armed Forces General Hospital. The obtained results were as follows : 1. The gunshot wounds were directed from submental area to dorsum of nose(3 cases), frontal area(1 case), orbit(1 case), infraorbital area (1 case), and lateral to nasal wing(l case). The shape of inlet in gunshot wounds were round (diameter: l-3cm) and that of outlet were oval shape(size : inlet

• Journal of the Korean Solar Energy Society
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• v.28 no.2
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• pp.28-33
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• 2008

The purpose of this study was experimentally to investigate thermal performance of heat pipe for evacuated tubular solar collector. Two sets of evacuated tubular solar collector with different condenser shape of heat pipe were prepared. The experiments were performed under the same operating condition with an indoor testing apparatus. Also, the experiments were carried out various testing conditions including inclination, flow rate, and incident heat flux. The results of thermal performance of collector with enlarged condenser showed that $F_R({\tau}{\alpha})$ was 0.6572 and $F_RU_L$ was -2.0086 at $40^{\circ}$. And the results of thermal performance of collector with straight condenser showed that $F_R({\tau}{\alpha})$ was 0.6233 and $F_RU_L$ was -1.4996 at the same inclined angle.